This bypass technique targets Cloudflare's Web Application Firewall (WAF) and is used to bypass XSS (Cross-Site Scripting) protections. The payload consists of three parts: 'oNlY=1' which is a junk attribute used to break pattern matching rules, 'oNeRrOr' which is written in mixed case to evade signature detection by the WAF, and the function call '(alert)(document.domain)' where using parentheses evades detection of function names commonly monitored by the WAF. Together, these tricks enable the payload to bypass Cloudflare's WAF and execute JavaScript alerts showing the current domain, demonstrating a successful XSS attack bypass. This shows how attackers can use invalid or unexpected syntax and casing techniques to evade WAF security rules.
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